Investigation of new surface exploration methods
There’s an old miners’ saying that goes “It’s dark in front of the pick”. This alludes to a fundamental problem: you can only know what things look like underground by actually looking at the rock. To this day, the principal means of obtaining information about subsurface geology is via boreholes.
This is where “GeoMetEr” comes in. The research project is being launched in mid-March 2023 by the Bundesgesellschaft für Endlagerung (BGE) – as the initiator and contracting body – in collaboration with a project group led by the Freiberg University of Mining and Technology. The BGE hopes the project will allow it to determine which exploration methods can provide reliable information as it moves towards identifying a repository site for high-level radioactive waste. To this end, the aim is to develop and explore geophysical measurement procedures for surface exploration programmes. These procedures are intended to facilitate the minimally invasive exploration of siting regions – that is, exploration in the most gentle manner possible for the rock – in the second phase of the site selection procedure.
A focus on three measurement techniques
The research project is being carried out in two research regions. In the BGE’s view, neither of these can be considered as a possible future repository site given the exclusion criteria set out in the Repository Site Selection Act (StandAG). They will therefore no longer be considered in the site search procedure by the BGE. These regions will be used to examine the suitability and informative value of various geophysical measurement techniques and combinations of techniques in greater detail. This work will focus on three measurement techniques in particular: seismic, magnetic and electromagnetic measurements from the air, as well as one research borehole per research region.
One research region is located close to the municipality of Langenweißbach im Erzgebirge. There, the planned measurements will serve to analyse the crystalline host rock. Work is still underway on finding a second research region in the Opalinus clay in the district of Sigmaringen, southern Baden-Württemberg. Here, the various measurement procedures are intended to facilitate closer investigation of the protective effect of an overburden.
First measurements planned
With a view to defining the second research region, the first simple measurements will be carried out from 13 to 17 March at single points in order to identify possible electromagnetic interference effects (e.g. due to transmitter masts and pylons). To this end, two colleagues from the University of Münster, which is one of the project partners, will be out and about in the district in a car or van. The measurements will be carried out in forests of the towns of Mengen, Meßkirch, Pfullendorf and Sigmaringen and the municipalities of Bingen, Hohentengen, Krauchenwies and Sauldorf. Based on the scientific evaluations of these measurements, a research region measuring 100 to 150 square metres will then be defined.
About the BGE
The BGE is a federally owned company within the portfolio of the Federal Environment Ministry. On 25 April 2017, the BGE assumed responsibility from the Federal Office for Radiation Protection as the operator of the Asse II mine and the Konrad and Morsleben repositories. Its other tasks include searching for a repository site for the disposal of high-level radioactive waste produced in Germany on the basis of the Repository Site Selection Act, which entered into force in May 2017. The managing directors are Stefan Studt (Chair), Steffen Kanitz (Deputy Chair) and Dr Thomas Lautsch (Technical Managing Director).